The cable television industry broadcasts audio and video programming, and other services, into homes, businesses, and to other subscribers using a broadband, frequency division multiplexed signal over multiple media types, including RF, fiber optic, and coaxial cable media (FIG. 1). Typically, the last leg of the transmission is over coaxial cable into the subscriber premises and all programming services are available over this cable. Signals representing a multitude of programmed broadcasts are typically frequency division multiplexed within the 54 megahertz (MHz) to 860 megahertz frequency range. Moreover, in recent years, additional services have been proposed that further crowd the available spectrum below 1 gigahertz (GHz) that is typically achievable in much of the installed coaxial media. This includes proposals to use signaling in the 8 MHz to 46 MHz range, and 70 to 130 MHz range for two-way data signaling (FIG. 2). Because frequency assignments in the various cable television frequency standards may not coincide with the tuning capability of a subscriber's television set, typical subscriber premise equipment includes a separate box (the “cable converter”) which is used to map incoming channels to another channel (typically channel 3 or 4) for which the subscriber's television set is capable of receiving (FIG. 3A). Use of a cable converter may be precluded if the subscriber has cable-ready equipment on the premises that is compatible with the cable signal being provided by the cable operator (FIG. 3B). However, in some cases, another class of cable converter may be required even in these cases to address frequency incompatibilities and/or signal decryption requirements.
In the case of subscription services (e.g. subscription movie channels) or Pay-per-View (PPV) programming, this necessitates the use of encryption technology that encrypt signals to restrict program access to authorized subscribers since access to the uncoded PPV and subscription signals would be possible otherwise within the customer premises, and would, therefore, represent a significant system security weakness. In turn, the use of encryption technology on these signals requires the placement of a decoder/descrambler/tuner box (or boxes) within the subscriber premises (FIG. 3C). These decoder boxes, and the conventional cable converter box, represent an equipment liability for the cable operator for which there are substantial annular losses due to theft, damage, and other forms of loss. And, because this equipment is typically installed on the customer premises, access for installation, service, and removal is limited to mutually convenient scheduled hours, which typically leads to increased service costs as a result of missed appointments. Further, because the equipment is typically installed on the customer premises, exposure to damages sustained due to equipment tampering adds to the liability that a cable operator must absorb in the cost of doing business.
The objects of this invention include reducing costs to the cable operator by reducing exposure to equipment losses by reducing (and, ultimately, eliminating) subscriber premises equipment (SPE) costs, and eliminating the requirement and cost associated with signal scrambling into the subscriber premises. The invention accomplishes this by providing on-demand cable programming using out-of-band signaling techniques to provide channel selection data from equipment located within the subscriber premises to signal-server equipment located outside the subscriber premises. Since, in the invention, a substantial majority of the SPE, formerly located within the subscriber premises, is moved outside the subscriber premises, there is increased equipment security, increased signal security, and the adjunct benefit of increased accessibility of equipment for servicing (thereby reducing loses due to rescheduled field service calls).